I have a Lenovo desktop we bought maybe 18 months ago, with Windows 7 / 32-bit. The main user is my wife, and my kids use it occasionally too. We have some photos, a lot of E-Mails, some documents, but nothing in my mind that should be clogging the entire system. For the most part the computer ran just okay since the day we bought it - not super slow but never particularly fast (we have a cable connection). But suddenly a few days ago it just started running extremely slow for no apparent reason. It's slow on all applications, and a couple times when I restarted, it froze up on a black screen and didn't load up Windows. I've noticed the hard drive seems to be constantly working, on what I don't know. Possibly something is running in the background or somebody did something, but I'm at a total loss on what to do.

I'm sure I need to provide more information but I'm not sure what. If someone is looking to provide an answer but needs more info, please let me know and I will provide it. Thanks in advance for anyone who can help out. I'm hoping it's an easy solution.

It sounds like you could have a virus or other malware. Get your antivirus program up to date and boot into Safe Mode. Note that some viruses can hide themselves from your antivirus program in normal mode, so you really need to scan in Safe Mode. To get into Safe Mode when you first power up, hit F8 about once a second until you get the menu and select Safe Mode. Then run a full system scan.- Microsoft has suggestions and offerings at http://windows.microsoft.com/en-US/windows7/how-do-I-remove-a-computer-virus- MS forum moderator Keith has some suggestions along this line at http://answers.microsoft.com/en-us/windows/forum/windows_7-performance/windows-explorer-has-stopped-working/6ab02526-5071-4dcc-895f-d90202bad8b3- If that fixes it, fine. If not, use System Restore to go back to a date prior to the beginning of the problem. To run System Restore, click Start -> Programs -> Accessories -> System Tools -> System Restore. Click the box that says Show more restore points. - You can check for corrupted system files. Open an administrator command prompt and run SFC if the above doesn't help. Click START, then type CMD in the search box, right-click CMD.EXE and click Run as administrator. Then from the command prompt type sfc /scannow.- Finally if all else fails, you can check the rather cryptic system event log. To do that click Start -> Control Panel -> Administrative Tools -> Event Viewer. Once in Event Viewer click on the system log and scroll through the entries looking for those flagged "error" to see if you can find hints as to where the problem could be. ` When you get your system back in good working order, I urge you to back your system up to an external hard drive and make regular periodic updates to it.- I hope this helps. Good luck.

This situation could be created by any number of things. Look in startup, START, RUN type in MSCONFIG press enter, see what is running at startup. Slow booting can be created by too many applications set to run at boot. To see IF there are applications running, CTRL ALT DELETE click TASK MANAGER, if unwanted items are running, highlight and click END TASK. You didn't say what you might be running for security software, lack of such could allow unwanted items, such as malware and or spyware, to infiltrate the system and create a myriad of issues including slowdowns. Just from your descrition I would suspect malware might be your problem although it may be something else. You said your HDD might be loaded up, check drive space if you haven't already,in My Computer, right click on main drive, usually C, click on Properties, that should give you an approximation of available space on HDD . For a malware sweep download MALWAREBYTES (as long as the system will allow you) and run it to see if it picks anything up, follow the instructions and if malware bugs are present, try the removal. If the system will not allow you to do this, go to another computer(clean) download MWB save to a flash drive or CD boot the suspect system into SAFE MODE WITH NETWORKING and run MWB fron there via the FD or CD.IF the HDD should be found to be the issue( I sort of doubt that unless you have a small drive) transfer data, photos etc. to an external source CD/DVD external drive(s) and purge some of those items from the system

Thanks to both of the people who posted answers. There are some good solutions in here. I will try them when I get home tonight, and let you know how they work. I actually do back up my system periodically, not to a hard drive but to the cloud through a software I bought called MyPCBackup. Maybe this has something to do with it? When I first got this program about a year ago, it slowed down the system badly every time it backed me up. I couldn't figure out how to back up just the stuff that has been changed rather than everything on the entire hard drive.

An update: I ran a full scan with my anti-virus software (Kaspersky) and I ran Malwarebytes, both while in safe mode, but neither one found anything. Actually sorry, first I ran Malwarebytes in normal mode and it found one thing that I deleted. Then I ran both in safe mode, they found nothing, and the speed did not improve.

My hard drive is nowhere close to full, and I have very little running at startup. I have a bunch of stuff on the Services tab in MSCONFIG, and I tried to do the clean boot thing but the computer was working so slowly that I wasn't able to get it done. I may need to try it again.

Meanwhile I'm also finding that sometimes when I restart the computer it's not loading up properly. Sometimes I get a message like "Reboot and insert boot media" (something like that), and sometimes it says "Disk Read Error, press CTRL+ALT+DEL". Things I've looked at say this could be a sign that the hard drive is crashing, others say like you folks that this sounds like a virus or malware.

Finally, I ran TDSSKILLER through Kaspersky, to check for the Rootkit malware but it didn't find anything. Currently I'm running a full system scan using Microsoft Malicious Software Removal Tool, and I'm 90 minutes in but it hasn't found anything. So even though all signs seem to point to a virus or malware, it's not looking likely that that's what the problem is.

Based on the above, any further thoughts? As always, thanks to everyone for your guidance.

I will try RKILL. What's very weird is yesterday my wife said the computer seemed to be running fine. I had run the Microsoft Malicious Software Removal Tool overnight, and I actually forgot to ask her if it caught anything. The hard drive appeared to be quieter. Then last night my son was using the computer and it started freezing up again. So first of all does the fact that the condition "comes and goes" help with the diagnosis? Second, I should be able to pinpoint a pretty clear time in the Event Log to see what the problem is, right?

Was all set to have the hard drive replaced, and suddenly this morning I'm able to get into Windows & it's moving relatively quickly. The hard drive is still making noise as though it is constantly spinning.

I'm confused that the situation seems to come and go so suddenly, without any reason I can figure out. Does this sound like the sign of a virus / malware, so I should keep working on that, or the sign of failing hardware?

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